Best Practices for Rman Catalog Upgrade

Hi, everyone!

I have many databases in Oracle 11g registered in RMAN Catalog (Database and Catalog in Oracle 11g).

I am going to do an Upgrade all databases to 12c on at the time.

Which the best practices recommended for that?

1) Create a new schema/catalog and I can execute the upgrade catalog in this one to run backups all databases 12c and the remainder the databases 11g can continue to execute in old schema/catalog 11g;

2)  Create a new instance for Rman Catalog already in Oracle 12c and I can register the databases 12c in this one and the remainder the databases 11g can continue to execute in old schema/catalog 11g;